High-pressure fluid-jet cutting device and method with abrasive removal system

ABSTRACT

A fluid jet-cutting machine with an abrasive particle removal device and method. In one embodiment, the fluid-jet cutting machine has a nozzle and a carrier assembly attached to the nozzle to move the nozzle along a cutting path. A high-pressure fluid source and an abrasive particle source are coupled to the nozzle to generate an abrasive fluid-jet having a fluid and a plurality of abrasive particles for cutting a work-piece. The cutting machine also has a particle removal including, tank aligned with the nozzle, a settling container, and a fluid transport mechanism to transport fluid from the tank to the settling container. The tank includes at least one compartment configured to receive the fluid and the abrasive particles of the fluid-jet along at least a portion of the cutting path. Additionally, the compartment is configured to control fluid flow within the compartment so that the fluid-jet suspends, and maintains the suspension, of at least a substantial portion of the abrasive particles in the one compartment without additional mechanical agitation. The fluid transport mechanism can include a conduit with a first end in fluid communication with the compartment and a second end outside of the compartment in fluid communication with the settling container. In operation, a portion of the fluid with suspended abrasive particles in the compartment is transported through the conduit and into the settling container. The abrasive particles from the transported portion of fluid settle to a lower portion of the settling container while a clarified fluid is removed from the settling container.

TECHNICAL FIELD

[0001] The present invention relates to fluid-jet cutting devices andmethods, and more particularly to such devices including an abrasiveremoval system.

BACKGROUND OF THE INVENTION

[0002] Fluid-jet cutting devices are often used to cut metal parts,fiber-cement siding, stone and many other materials. A typical fluid-jetcutting machine has a high-pressure pump to provide a high-pressurefluid source, and a nozzle is coupled to the high-pressure fluid sourceto generate a cutting-jet from the nozzle. The nozzle is also attachedto a carrier assembly that moves the nozzle along a desired cuttingpath, and a catch tank is aligned with the nozzle throughout the cuttingpath. An abrasive particle source may be coupled to the nozzle to impartabrasive particles to the cutting-jet. The fluid is typically water, andthe abrasive particles are typically garnet.

[0003] In operation of such a fluid-jet cutting machine, a work-piece ispositioned between the nozzle and the catch tank. The carrier assemblymoves the nozzle along the cutting path, and the high-pressure fluidsource and abrasive particle source generate an abrasive cutting-jetprojecting from the nozzle. As the cutting-jet passes through thework-piece, the catch tank receives the wastewater and abrasiveparticles of the spent cutting jet The abrasive particles generallyaccumulate in the catch tank, and the waste water generally flows out ofthe catch tank.

[0004] One concern with fluid-jet cutting systems is that the abrasiveparticles must be removed from the catch tank. The devices and methodsfor removing abrasive particles from catch tanks typically depend uponthe size of the catch tanks. In general, small catch tanks are typicallyless than 2′×4′, and large catch tanks are typically greater than 4′×8′.

[0005] Conventional techniques for removing abrasive particles fromsmall catch tanks generally allow the wastewater to simply overflow thesmall catch tanks. Although a portion of the abrasive particles areremoved from small catch tanks with the overflowing wastewater, abrasiveparticles still accumulate in small catch tanks. The remaining abrasiveparticles are typically removed from small catch tanks by: (1) stoppingthe cutting-jet to allow the abrasive particles to settle; and (2)shoveling or dumping the abrasive particles from the catch tank.

[0006] One problem with conventional techniques for removing abrasiveparticles from small catch tanks is that the cutting machine must beshut down for a period of time to allow the abrasive particles tosettle. Removing abrasive particles from small catch tanks mayaccordingly result in a significant amount of down-time in a cuttingoperation. Another problem with removing abrasive particles from smallcatch tanks is that it is inconvenient and labor intensive to shovel ordump the abrasive particles from the tanks. Therefore, removing abrasiveparticles from small catch tanks reduces the efficiency and productivityof fluid-jet cutting processes.

[0007] Conventional techniques for removing abrasive particles fromlarge catch tanks are different than those for small catch tanks. Oneconventional abrasive removal system for large catch tanks is a conveyorrake that moves across the bottom of a large catch tank and up adischarge side of the tank. To most effectively operate a conveyor rake,the abrasive particles must settle to the bottom of the tank. Theconveyor then carries the abrasive particles from the bottom of the tankand over the discharge side of the tank. One potential problem withconveyor rakes, therefore, is that they may need to be operated when thecutting-jet is shut down causing down-time. Another problem withconveyor rakes is that they may be cut by the cutting-jet during thecutting process if the cutting-jet passes over the portion of theconveyor rake at the discharge side of the catch tank. Additionally,conveyor rake removal systems may be relatively expensive units withmany moving components that may fail after extended use. Thus, conveyorrake systems for removing abrasive particles from large catch tanks haveseveral drawbacks.

[0008] Another conventional system for removing abrasive particles fromlarge catch tanks is a continuous centrifugal system that has a largepump in the catch tank and a centrifugal separator outside of the catchtank. The large pump agitates the wastewater to suspend the abrasiveparticles in the catch tank. The wastewater and the suspended abrasiveparticles are then pumped to a centrifuge, such as a hydrocycloneseparator, to separate the abrasive particles from the wastewater. Onedrawback of this device is that large, expensive pumps are required tomaintain the abrasive particles in suspension in the wastewater. Anotherdrawback of this abrasive removal system is that a significant amount ofenergy is required to operate such large pumps. Additionally,hydrocyclone separators are also relatively costly devices that requireadditional resources to operate and maintain. Thus, centrifugal removalsystems also have several drawbacks.

SUMMARY OF THE INVENTION

[0009] The invention is generally directed toward fluid jet-cuttingmachines and abrasive particle removal devices. In one embodiment, afluid-jet cutting machine has a nozzle and a carrier assembly that movesthe nozzle along a cutting path. A high-pressure fluid source and anabrasive particle source are coupled to the nozzle to generate anabrasive cutting-jet having a fluid and a plurality of abrasiveparticles. In general, the fluid can be water and the abrasive particlescan be composed of garnet.

[0010] The cutting machine also has a particle removal device includinga tank aligned with the nozzle, a settling container, and a fluidtransport mechanism to transport fluid from the tank to the settlingcontainer. The tank includes at least one compartment configured toreceive the fluid and the abrasive particles of the cutting-jet along atleast a portion of the cutting path. Additionally, the compartment isconfigured to control fluid flow within the tank so that the cutting-jetcontinuously suspends at least a substantial portion of the abrasiveparticles in the one compartment without additional mechanicalagitation. The compartment itself, for example, can be sized and/orshaped so that the jet energy alone maintains the abrasive particles insuspension. The fluid transport mechanism can include a conduit with afirst end in fluid communication with the compartment and a second endoutside of the compartment in fluid communication with the settlingcontainer.

[0011] In operation, a portion of the fluid with suspended abrasiveparticles in the compartment is transported through the conduit and intothe settling container. For example, a fluid drive system may be coupledto the conduit to draw fluid from the compartment and through theconduit. The abrasive particles from the transported portion of fluidsettle to a lower portion of the settling container while a clarifiedfluid is removed from the settling container. The clarified fluid mayalso be pumped back to the catch tank.

BRIEF DESCRIPTION OF THE DRAWINGS

[0012]FIG. 1 is a schematic isometric view of a fluid-jet cuttingmachine with a cut-away view of one embodiment of an abrasive particleremoval system.

[0013]FIG. 2 is a partial cross-sectional view of the abrasive removalsystem of the fluid-jet cutting machine shown in FIG. 1.

[0014]FIG. 3 is a partial cross-sectional view of another embodiment ofan abrasive particle removal system for a fluid-jet cutting machine.

[0015]FIG. 4 is a partial cross-sectional view of another embodiment ofan abrasive particle removal system for a fluid-jet cutting machine.

[0016]FIG. 5 is a partial cross-sectional view of another embodiment ofan abrasive particle removal system for a fluid-jet cutting machine.

[0017]FIG. 6 is a partial cross-sectional view of another embodiment ofan abrasive particle removal system for a fluid-jet cutting machine.

[0018]FIG. 7 is a schematic isometric view of another fluid-jet cuttingmachine with a cut-away view of another embodiment of an abrasiveparticle removal system.

DETAILED DESCRIPTION OF THE INVENTION

[0019] The present invention is directed toward devices and methods forremoving abrasive particles from fluid-jet cutting machines. Manyspecific details of certain embodiments of the invention are set forthin the following description and in FIGS. 1-7 to provide a thoroughunderstanding of such embodiments. One skilled in the art, however, willunderstand that the present invention may have additional embodiments,or that the invention may be practiced without several of the detailsdescribed in the following description.

[0020]FIG. 1 is a schematic isometric view of a fluid-jet cuttingmachine 10. In this embodiment, the cutting machine 10 includes acutting head 20 with a carrier assembly 21 and a nozzle 22 attached tothe carrier assembly 20. A high-pressure fluid source 24 and an abrasiveparticle source 26 are coupled to the nozzle 22 to generate an abrasivecutting-jet 28 projecting from the nozzle 22. Additionally, the cuttingmachine 10 also includes a work-piece support structure 30 with a numberof support members or beams 32 attached to a frame 33. In operation, thecarrier assembly 21 moves the nozzle 22 along desired X-Y coordinates(arrows M) to move the cutting-jet 28 along a desired cutting path Pwith respect to a work-piece W. One suitable cutting head 20 is theBengal 4×4 and Paser 3 System manufactured by Flow InternationalCorporation of Kent, Wash.

[0021] The cutting machine 10 also includes an abrasive particle removalsystem 40. In one embodiment, the abrasive particle removing system 40has a catch tank 42 under the support structure 30, a fluid transportmechanism 44 in the catch tank 42, and a settling container 46 coupledto the fluid transport mechanism 44. As described in greater detailbelow, the abrasive particle removal system 40 continuously removesabrasive particles from the catch tank 42 without using mechanicalagitators to suspend the abrasive particles in the waste fluid.

[0022] The catch tank 42 preferably has a bottom panel 50, first andsecond side-walls 51 a and 51 b projecting upward from opposing sides ofthe bottom panel 50, and first and second end-walls 51 c and 51 dprojecting upward from opposing ends of the bottom panel 50. The firstand second side-walls 51 a and 51 b are attached to the first and secondend-walls 51 c and 51 d to form a large cavity. The catch tank 42 alsoincludes a central divider 52 extending longitudinally within the tank42, and a plurality of crossing dividers 54 extending transverse to thecentral divider 52. The dividers 52 and 54 define a plurality ofcompartments 56 (identified by reference numbers 56 a-56 f) in the tank42.

[0023] The compartments 56 receive the waste-fluid 12 and the abrasiveparticles of the cutting-jet 28. Additionally, each compartment 56 isconfigured to control the fluid flow within the tank 42. For example,when the cutting-jet 28 is aligned with compartment 56 b, the dividers52 and 54 defining this compartment control the fluid flow such that thecutting-jet 28 alone suspends a significant portion of the abrasiveparticles in the waste-fluid 12. As such, by dividing the tank 42 intosmaller compartments 56, the cutting-jet 28 maintains at least asubstantial portion of the abrasive particles in suspension in thewaste-fluid 12 within a particular compartment aligned with thecutting-jet 28 without additional mechanical agitation. In general, eachcompartment is approximately between 1′×1 and 4′×8′, and more preferablyabout 2′×4′. As explained in more detail below, the fluid transportmechanism 44 continuously removes waste-fluid 12 and abrasive particlesfrom the compartments 56.

[0024]FIG. 2 is a partial cross-sectional view of a portion of theremoval system 40 in which the fluid transport system includes a numberof conduit sections 60 (identified by reference numbers 60 a and 60 b).The conduit sections 60 are configured in a serial arrangement totransport waste fluid and abrasive particles to the settling container46 from the compartments 56 a, 56 b and 56 c. The conduit sections 60include at least a first conduit section 60 a having a first end 62positioned in the lower portion of compartment 56 b and a second end 64positioned in compartment 56 a. The first conduit section 60 a also hasa first intake opening 66 proximate to the bottom panel 50, a secondintake opening 68 located to receive a fluid flow from a conduit sectionfrom the adjacent upstream compartment 56 c, and a vent 67 toward thesecond end 64. The second intake opening 68, for example, can be afunnel. The conduit sections 60 can also include a second conduitsection 60 b similar to the first conduit section 60 a, and thus likereference numbers refer to like components. The second conduit section60 a has a first end 62 positioned in the lower portion of compartment56 a and a second end 64 coupled to the settling container 46. Thesecond intake opening 68 of the second conduit section 60 b is locatedto receive a first fluid flow F₁ from the second end 64 of the firstconduit section 60 a. Accordingly, the first and second conduit sections60 a and 60 b define a conduit that transports waste fluid and abrasiveparticles from the compartments 56 a and 56 b to the settling container46.

[0025] To generate fluid flows through the conduit sections 60, a fluiddrive system 70 is preferably coupled to the conduit sections 60 todrive the waste-fluid 12 and the abrasive particles 14 through theconduit sections 60. In this particular embodiment, the fluid drivesystem 70 includes a fluid driver 71, a primary line 72 coupled to thefluid driver 71, and a plurality of branch feed lines 74 coupled to theprimary line 72. The fluid driver 71 can be a pressurized gas source,such as an air compressor. The primary line 72 generally passes throughthe dividers 52 and 54 to supply pressurized gas to all of thecompartments 56. The branch feed lines 74 are attached to the conduitsections 60 below the fluid level of the waste-fluid 12 in thecompartments 56. In operation, the pressurized gas source 71 injects agas 78, such as air, into the conduit sections 60. The gas 78accordingly rises through the vertical portions of the conduit sections60 drawing waste-fluid 12 and any abrasive particles 14 suspended in thewaste-fluid 12 through the conduit sections 60. The gas 78 passesthrough the vents 67, while the fluid continues to flow through theconduit sections 60. The fluid drive mechanism 70, therefore, generatesthe first fluid flow F₁ through the first conduit section 60 a and asecond fluid flow F₂ through the second conduit section 60 b.

[0026] The settling container 46 receives the second fluid flow F₂ fromthe second conduit section 60 b. The settling container 46 can have adisposable drum 90 and a shroud 92 attached to a rim of the drum 90. Theshroud 92 has an inlet 94 coupled to the second end 64 of the secondconduit section 60 b, and the shroud 92 has an outlet 96 through which aclarified fluid 16 flows from the settling container 46. As the secondfluid flow F₂ enters the shroud inlet 94, the abrasive particles 14 falldownward and form an abrasive particle accumulation 18 in the drum 90.The clarified fluid 16 accordingly rises to the shroud outlet 96. Theclarified fluid 16 can then be pumped beck to the compartments 56 in thecatch tank 42 (shown schematically in FIG. 1), or it can overflow thecontainer 46 in flow into a drain.

[0027] Referring to FIGS. 1 and 2 together, the abrasive removal system40 removes abrasive particles from at least one of the compartments 56as the cutting-jet 28 moves along the cutting path P. As the cutting-jet28 passes over the compartment 56 b, the cutting-jet 28 agitates thewaste-fluid 12 to suspend a significant portion of the abrasiveparticles 14 within the compartment 56 b without additional mechanicalagitation. The compartment 56 b allows the cutting-jet 28 to adequatelysuspend the abrasive particles 14 in the waste-fluid 12 withoutadditional mechanical agitation because the dividers 52 and 54concentrate the turbulence generated by the cutting-jet 28 and containthe abrasive particles 14 within the relatively small volume ofcompartment 56 b. The fluid flow F₁ through the first conduit section 60a accordingly draws a portion of the waste-fluid 12 and the suspendedabrasive particles 14 through the first conduit section 60 a. The firstfluid flow F₂ exits from the first conduit section 60 a, and the secondfluid flow F₂ in the second conduit section 60 a draws the first fluidflow F₁ into the second intake opening 68 of the second conduit section60 b. The suspended abrasive particles 14 from compartment 56 b are thustransported to the settling container 46 through the first and secondconduit sections 60 a and 60 b. The clarified fluid 16 in the settlingcontainer 46 can then be returned to the catch tank 42 to maintain adesired fluid level within the tank 42, or the clarified fluid 16 can bedisposed of in an environmentally safe manner.

[0028] One aspect of the cutting machine 10 is that it reduces thedown-time to remove abrasive particles from the catch tank 42 comparedto many conventional removal systems. The abrasive particle removalsystem 40 continuously removes abrasive particles from the catch tank 42without using additional mechanical agitators to suspend the abrasiveparticles 14 in the waste fluid 12. By continuously removing theabrasive particles from the catch tank 42, the cutting machine 10 doesnot need to be shut down for cleaning the catch tank 42. Thus, comparedto conventional removal techniques that shut down the cutting machinesto allow the abrasive particles to settle, the abrasive particle removalsystem 40 reduces the down-time of the cutting machine 10.

[0029] Additionally, another aspect of the cutting machine 10 is that itis generally less expensive to manufacture and operate than conventionalcutting machines with centrifugal abrasive removal systems. As set forthabove, conventional centrifugal abrasive systems use large, expensivepumps to suspend the abrasive particles in large catch tanks. Theabrasive particle removal system 40, however, divides the catch tank 42into a plurality of smaller compartments 56 that control the fluid flowwithin the catch tank 42 so that the cutting-jet 28 suspends theabrasive particles in an active compartment 56 without additionalmechanical agitation. The abrasive particle removal system 40 canaccordingly use inexpensive, low volume fluid drive systems instead ofthe large, expensive pumps. Thus, the abrasive particle removal system40 is less expensive to manufacture and operate than large capacitycentrifugal abrasive removal systems.

[0030] Still another aspect of the abrasive particle removal system 40is that it is reliable and does not require a significant amount ofmaintenance. The removal system 40 has very few moving components, andnone of the moving components directly contact the abrasive particles.In contrast to the removal system 40, the conventional conveyor rake andcentrifugal removal systems have several moving parts that directlycontact the abrasive particles. As such, the abrasive particles can weardown many important components of conventional removal systems (e.g.,conveyor rakes, pumps and centrifugal separators). Thus, because theremoval system 40 has very few moving parts, it is a reliable systemthat does not require a significant amount of down-time for maintenance.

[0031]FIG. 3 is a partial cross-sectional view of another embodiment ofan abrasive particle removal system 140. The abrasive particle removalsystem 140 illustrated in FIG. 3 is similar to the removal system 40illustrated in FIG. 2, and thus like reference numbers refer to likecomponents. Referring to FIG. 3, a first conduit section 160 a has afirst end 162 positioned in a lower portion of compartment 56 b and asecond end 164 positioned in compartment 56 a. Additionally, a secondconduit section 160 b has a first end 162 positioned in compartment 56 aand a second end 164 coupled to the shroud inlet 94. Each conduitsection 160 a and 160 b has a back-flush valve 69 to control the fluidflows through the conduit sections. Unlike the removal system 40 of FIG.2, the first ends 162 of the conduit sections 160 have a single intakeopening 166. In operation, therefore, the gas 78 from the pressurizedgas source 71 rises through the conduit sections 160 a and 160 b togenerate the first and second flows F₁ and F₂.

[0032]FIG. 3 also illustrates the operation of the back-flush valves 69in the conduit sections. For example, the abrasive particles in thefirst flow F₁ may accumulate in an abrasive particle accumulation 118 incompartment 56 a at the first end 162 of the second conduit section 160b. The abrasive particle accumulation 118 in compartment 56 a mayeventually block the intake opening 166 of the second conduit section160 b. To clear the intake opening 166 in compartment 56 a, theback-flush valve 69 in the second conduit section 56 b is closed. Thepressure in the second conduit section 160 b upstream from theback-flush valve 69 builds until it blows backward through the intakeopening 166. The pressurized gas source 71 accordingly should operate at70-150 psi to provide sufficient pressure to blow abrasive particleaccumulations away from the first end 162 of the second conduit section160 b.

[0033]FIG. 4 is a partial cross-sectional view of still anotherembodiment of an abrasive particle removal system. The abrasive particleremoval system 240 has conduit sections 260 (identified by referencenumbers 260 a and 260 b) with first ends 62 coupled directly to theprimary line 72 of the fluid drive system 70. As such, the gas 78 risesthrough the vertical portions of the conduit sections 260 to draw thefluid through the first and second intake openings 66 and 68.Additionally, a second back-flush valve 79 may be positioned in theprimary line 72 after the connection of each conduit section 260. Toclear a first conduit section 260 a, for example, the back-flush valve69 in the first conduit section 260 a and the back-flush valve 79 incompartment 56 b are closed to allow pressure to build within the firstconduit section 260 a.

[0034]FIG. 5 is a partial cross-sectional view illustrating anotherabrasive removal system 340 having a conduit 360 with a main conduitsection 361 and a plurality of compartment conduit sections 363(indicated by reference numbers 363 a and 363 b). For example, a firstconduit section 363 a has a first end 362 in the lower portion ofcompartment 56 b and a second end 364 attached to the main conduitsection 361. Similarly, a second conduit section 363 b has a first end362 in the lower portion of compartment 56 a and a second end 364coupled to the main conduit section 361. In operation, therefore, thefluid drive system 70 draws fluid through the compartment conduitsections 363 and into the main conduit section 361 such that a finalfluid flow F_(f) flows through the shroud inlet 94.

[0035]FIG. 6 is a partial cross-sectional view illustrating stillanother abrasive removal system 440 in which the conduit sections 440(identified by reference numbers 440 a and 440 b) operate in parallel toindividually deliver separate fluid flows F₁ and F₂ into the settlingcontainer 46. In this embodiment, a first fluid section 440 a has afirst end 442 a positioned in a lower portion of compartment 56 b and asecond end 444 a coupled to the shroud inlet 94. A second conduitsection 440 b has a first end 442 b positioned in compartment 56 a and asecond end 444 b also coupled to the shroud inlet 94. Thus, in thisembodiment, a number of parallel fluid flows are delivered to thesettling container 46.

[0036]FIG. 7 is a schematic isometric view of another abrasive particleremoval system 540 for use with the cutting machine 10. The removalsystem 540 has a catch tank 542 with a longitudinal divider 552extending longitudinally along the tank 542 and a number of crossingdividers 554 extending transverse to the longitudinal divider 552. Thesidewalls 551 project upward from a bottom panel 550 to an elevationabove the top edges of the dividers 552 and 554 such that the level ofthe waste-fluid 12 can be above the top edges of the dividers. Thedividers 552 and 554 may thus be baffles that define a plurality ofcompartments 556 (identified individually by reference numbers 556 a-556f) that restrict the fluid flow from one compartment to another, butstill allow the fluid to flow over the baffles.

[0037] From the foregoing it will be appreciated that, although specificembodiments of the invention have been described herein for purposes ofillustration, various modifications may be made without deviating fromthe spirit and scope of the invention. For example, the fluid driver 71of the fluid drive system 70 can be a pump or an impeller instead of apressurized gas source to drive a fluid through the primary line 72 andfeed lines 74. Additionally, the removal systems could also be used toremove other solids from a catch tank generated by abrasive ornon-abrasive cleaning and/or cutting operations. Such additionalapplications may be separating paint chips, dirt and other solids from acatch tank in ship cleaning, building cleaning and many other cleaningapplications. Accordingly, the invention is not limited except as by theappended claims.

1. A fluid-jet cutting machine, comprising: a nozzle adapted to be coupled to a high-pressure fluid source and an abrasive particle delivery device, the nozzle being configured to project an abrasive fluid-jet; a carrier assembly attached to the nozzle to move the nozzle and the fluid-jet along a cutting path; a tank aligned with the nozzle, the tank including at least one compartment configured to receive the fluid and the abrasive particles of the fluid-jet along at least a portion of the cutting path and to control fluid flow out of the one compartment, the controlled fluid flow of the one compartment and the fluid-jet maintaining at least a substantial portion of the abrasive particles in suspension in the fluid in the one compartment without additional mechanical agitation; a fluid transport mechanism including a conduit, the conduit having a first end in fluid communication with the one compartment and a second end outside of the one compartment; and a settling container separate from the one compartment, the second end of the conduit being in fluid communication with the settling container, a portion of the fluid with suspended abrasive particles in the one compartment being transported through the conduit from the one compartment into the settling container, and the abrasive particles from the transported portion of fluid settling to a lower portion of the settling container while a clarified fluid is removed from the settling container through an outlet of the settling container.
 2. The fluid-jet cutting machine of claim 1 wherein the first end of the conduit is positioned at a lower portion of the one compartment and the second end of the conduit is positioned below the first end and in the settling container, the fluid and the abrasive particles suspended in the fluid flowing through the conduit from the one compartment to the settling container under the influence of gravity.
 3. The fluid-jet cutting machine of claim 1 wherein the fluid transport mechanism further comprises a fluid drive system coupled to the conduit, the fluid drive system driving fluid and abrasive particles suspended in the fluid through the conduit to the settling container.
 4. The fluid-jet cutting machine of claim 3 wherein: the first end of the conduit is positioned in a lower portion of the one compartment; and the fluid drive system comprises a pressurized gas source attached to the conduit at a location below a fluid level in the one compartment, a gas from the pressurized gas source being injected into the conduit and the gas rising through at least a portion of the conduit, the rising gas drawing fluid and abrasive particles suspended in the fluid through the conduit from the one compartment to the settling container.
 5. The fluid-jet cutting machine of claim 4 wherein the fluid drive system further comprises a back-flush valve in the conduit between the second end and the location of attachment of the pressurized gas source, the back-flush valve being positionable in an open position to allow fluid to flow through the conduit and a closed position to allow pressure to build in the conduit for clearing a blockage of abrasive particles from the first end of the conduit.
 6. The fluid-jet cutting machine of claim 1 wherein the tank further includes a plurality of compartments and the cutting path moves with respect to the tank to pass across at least two of the plurality of the compartments, each compartment being configured to receive the fluid and the abrasive particles from the fluid-jet as the fluid-jet passes across each compartment and to control fluid flow to an adjacent compartment, and, while the fluid-jet passes across one of the compartments, the controlled fluid flow of the one of the compartments and the fluid-jet maintaining at least a substantial portion of the abrasive particles in suspension in the fluid in the one of the compartments without additional mechanical agitation.
 7. The fluid-jet cutting machine of claim 6 wherein the tank comprises: a bottom panel, a first side-wall projecting from one side of the bottom panel, a second side-wall projecting from another side of the bottom panel and juxtaposed to the first side-wall, a first end-wall projecting from one end of the bottom panel, and a second end-wall projecting from another end of the bottom panel and juxtaposed to the first end-wall, the first and second end-walls being attached to the first and second side-walls; and at least one divider extending across the tank between one of side-walls or the end-walls to divide the tank into at least two compartments.
 8. The fluid-jet cutting machine of claim 7 wherein the divider comprises a baffle around which a restricted fluid flow may pass from a first compartment to an adjacent second compartment.
 9. The fluid-jet cutting machine of claim 6 wherein: the tank comprises at least a first compartment and a second compartment; the conduit comprises at least a first conduit section and a second conduit section, the first conduit section having a first end positioned in a lower portion of the first compartment and a second end positioned in the second compartment, the second conduit section having a first end positioned in a lower portion of the second compartment and located to receive a first fluid flow from the first conduit section, and the second conduit section further including a second end open to the settling container; and the fluid transport system further comprises a fluid drive system coupled to the first and second conduit sections, the fluid drive system driving the first fluid flow through the first conduit section from the first compartment to the second compartment, and the fluid drive system driving a second fluid flow through the second conduit section from the second compartment to the settling container.
 10. The fluid-jet cutting machine of claim 9 wherein the fluid drive system comprises: a pressurized gas source; and a gas line coupled to the gas source, the gas line having a first segment attached to the first conduit section a location below a fluid level in the first compartment, and the gas line having a second segment attached to the second conduit section at a location below a fluid level of the second compartment, a gas from the pressurized gas source being injected into the first and second conduit sections and the gas rising through the conduit sections to draw the first and second fluid flows through the first and second conduit sections, respectively.
 11. The fluid-jet cutting machine of claim 10 wherein the fluid drive system further comprises: a first back-flush valve in the first conduit section between the second end of the first conduit section and the location of attachment of the first gas line, the first back-flush valve being positionable in an open position to allow the first fluid flow through the first conduit section and a closed position to allow pressure to build in the first conduit section for clearing a blockage of abrasive particles from the first end of the first conduit section; and a second back-flush valve in the second conduit section between the second end of the second conduit section and the location of attachment of the second gas line, the second back-flush valve being positionable in an open position to allow the second fluid flow through the second conduit section and a closed position to allow pressure to build in the second conduit section for clearing a blockage of abrasive particles from the first end of the second conduit section.
 12. An abrasive particle removal device for use with a fluid-jet cutting machine having a nozzle, a high-pressure fluid source and an abrasive particle source coupled to the nozzle to generate a fluid-jet having a fluid and a plurality of abrasive particles, and a carrier assembly attached to the nozzle to move the nozzle along a cutting path, the particle removal device comprising: a tank aligned with the nozzle, the tank including at least one compartment configured to receive the fluid and the abrasive particles of the fluid-jet along at least a portion of the cutting path and to control fluid flow out of the one compartment, the controlled fluid flow of one compartment and the fluid-jet maintaining at least a substantial portion of the abrasive particles in suspension in the fluid in the one compartment without additional mechanical agitation; a fluid transport mechanism including a conduit, the conduit having a first end in fluid communication with the one compartment and a second end outside of the one compartment; and a settling container separate from the one compartment, the second end of the conduit being in fluid communication with the settling container, a portion of the fluid with suspended abrasive particles in the one compartment being transported through the conduit from the one compartment into the settling container, and the abrasive particles from the transported portion of fluid settling to a lower portion of the settling container while a clarified fluid is removed from the settling container through an outlet of the settling container.
 13. The removal device of claim 12 wherein the first end of the conduit is positioned at a lower portion of the one compartment and the second end of the conduit is positioned below the first end and in the settling container, the fluid and the abrasive particles suspended in the fluid flowing through the conduit from the one compartment to the settling container under the influence of gravity.
 14. The removal device of claim 12 wherein the fluid transport mechanism further comprises a fluid drive system coupled to the conduit, the fluid drive system driving fluid and abrasive particles suspended in the fluid through the conduit to the settling container.
 15. The removal device of claim 14 wherein: the first end of the conduit is positioned in a lower portion of the one compartment; and the fluid drive system comprises a pressurized gas source attached to the conduit at a location below a fluid level in the one compartment, a gas from the pressurized gas source being injected into the conduit and the gas rising through at least a portion of the conduit, the rising gas drawing fluid and abrasive particles suspended in the fluid through the conduit from the one compartment to the settling container.
 16. The removal device of claim 15 wherein the fluid drive system further comprises a back-flush valve in the conduit between the second end and the location of attachment of the pressurized gas source, the back-flush valve being positionable in an open position to allow fluid to flow through the conduit and a closed position to allow pressure to build in the conduit for clearing a blockage of abrasive particles from the first end of the conduit.
 17. The removal device of claim 14 wherein: the first end of the conduit is positioned in a lower portion of the one compartment; and the fluid drive system comprises a pump attached to the conduit, the pump driving fluid through the conduit from the one compartment to the settling container.
 18. The removal system of claim 17 wherein the pump comprises a diaphragm pump.
 19. The removal device of claim 14 wherein: the first end of the conduit is positioned in a lower portion of the one compartment; and the fluid drive system comprises a motor with a drive shaft and an impeller attached to the drive shaft, the impeller being positioned with respect to the conduit to drive fluid through the conduit from the one compartment to the settling container.
 20. The removal device of claim 12 wherein the tank further includes a plurality of compartments and the cutting path moves with respect to the tank to pass across at least two of the plurality of the compartments, each compartment being configured to receive the fluid and the abrasive particles from the fluid-jet as the fluid-jet passes across each compartment and to control fluid flow to an adjacent compartment, and, while the fluid-jet passes across one of the compartments, the controlled fluid flow of the one of the compartments and the fluid-jet maintaining at least a substantial portion of the abrasive particles in suspension in the fluid in the one of the compartments without additional mechanical agitation.
 21. The removal device of claim 20 wherein the tank comprises a bottom panel, a side-wall projecting from the bottom panel to define a reservoir, and at least one divider in the reservoir to divide the tank into at least two compartments.
 22. The removal device of claim 20 wherein the tank comprises: a bottom panel, a first side-wall projecting from one side of the bottom panel, a second side-wall projecting from another side of the bottom panel and juxtaposed to the first side-wall, a first end-wall projecting from one end of the bottom panel, and a second end-wall projecting from another end of the bottom panel and juxtaposed to the first end-wall, the first and second end-walls being attached to the first and second side-walls; and at least one divider extending across the tank between one of side-walls or the end-walls to divide the tank into at least two compartments.
 23. The removal device of claim 22 wherein the divider comprises a baffle around which a restricted fluid flow may pass from a first compartment to an adjacent second compartment.
 24. The removal device of claim 20 wherein: the tank comprises at least a first compartment and a second compartment; the conduit comprises at least a first conduit section and a second conduit section, the first conduit section having a first end positioned in a lower portion of the first compartment and a second end positioned in the second compartment, the second conduit section having a first end positioned in a lower portion of the second compartment and located to receive a first fluid flow from the first conduit section, and the second conduit section further including a second end open to the settling container; and the fluid transport system further comprises a fluid drive system coupled to the first and second conduit sections, the fluid drive system driving the first fluid flow through the first conduit section from the first compartment to the second compartment, and the fluid drive system driving a second fluid flow through the second conduit section from the second compartment to the settling container.
 25. The removal device of claim 24 wherein the fluid drive system comprises: a pressurized gas source; and a gas line coupled to the gas source, the gas line having a first segment attached to the first conduit section a location below a fluid level in the first compartment, and the gas line having a second segment attached to the second conduit section at a location below a fluid level of the second compartment, a gas from the pressurized gas source being injected into the first and second conduit sections and the gas rising through the conduit sections to draw the first and second fluid flows through the first and second conduit sections, respectively.
 26. The removal device of claim 25 wherein the fluid drive system further comprises: a first back-flush valve in the first conduit section between the second end of the first conduit section and the location of attachment of the first gas line, the first back-flush valve being positionable in an open position to allow the first fluid flow through the first conduit section and a closed position to allow pressure to build in the first conduit section for clearing a blockage of abrasive particles from the first end of the first conduit section; and a second back-flush valve in the second conduit section between the second end of the second conduit section and the location of attachment of the second gas line, the second back-flush valve being positionable in an open position to allow the second fluid flow through the second conduit section and a closed position to allow pressure to build in the second conduit section for clearing a blockage of abrasive particles from the first end of the second conduit section.
 27. The removal device of claim 20 wherein: the tank comprises at least a first compartment and a second compartment; the conduit comprises a main section, a first conduit section coupled to the main section, and a second conduit section also coupled to the main section, the first conduit section having a first end positioned in a lower portion of the first compartment and a second end attached to the main section, the second conduit section having a first end positioned in a lower portion of the second compartment and a second end attached to the main section, and the main section having a discharge end open to the settling container; and the fluid transport system further comprises a fluid drive system coupled to at least one of the first, the second and the main conduit sections, the fluid drive system driving a first fluid flow through the first conduit section from the first compartment to the main section, and the fluid drive system driving a second fluid flow through the second conduit section from the second compartment to the main section, the first and second fluid flows passing through the discharge end of the main section to the settling container.
 28. The removal device of claim 20 wherein: the tank comprises at least a first compartment and at least a second compartment; the conduit comprises a first conduit section extending from the first compartment directly to the settling container and a second conduit section extending from the second compartment directly to the settling container, the first conduit section having a first end positioned in a lower portion of the first compartment and a second end open to the settling container, the second conduit section having a first end positioned in a lower portion of the second compartment and a second end open to the settling container; and the fluid transport system further comprises a fluid drive system coupled to the first and second conduit sections, the fluid drive system driving a first fluid flow through the first conduit section from the first compartment to the settling container, and the fluid drive system driving a second fluid flow through the second conduit section from the second compartment to the settling container.
 29. The removal system of claim 12 wherein the settling container comprises: a drum having a rim defining an opening of the drum; and a detachable shroud attached to the drum, the second end of the conduit being attached to the shroud to deposit the transported portion of the fluid into the drum, and the outlet of the settling container being positioned in the shroud, wherein the abrasive particles accumulate in the drum, and when the drum is full, the shroud is removed from the drum to be placed on another empty drum.
 30. A method of operating a fluid-jet cutting machine, comprising: projecting an abrasive fluid-jet having a plurality of abrasive particles in a fluid through a work-piece and into a compartment of a tank; maintaining a significant portion of abrasive particles in suspension in the fluid in the compartment without mechanical agitation other than the fluid-jet; transporting a portion of the fluid with suspended abrasive particles from the compartment to a settling container; and settling abrasive particles from the transported portion of fluid to leave an accumulation of abrasive particles in a lower portion of the settling container and a clarified liquid above the accumulation of abrasive particles in the settling container.
 31. The method of claim 30 wherein transporting the fluid comprises injecting a pressurized gas into a conduit section in the compartment below a fluid level in the compartment, the injected gas rising through a portion of the conduit section to generate a fluid flow through the conduit section that draws abrasive particles out of the compartment.
 32. The method of claim 30 wherein transporting the fluid comprises pumping a fluid through a conduit section to draw suspended abrasive particles out of the compartment.
 33. The method of claim 30 wherein: the fluid-jet cutting machine includes a catch tank with at least a first compartment and a second compartment, and a fluid transport system with a first conduit section having a first end in the first compartment and a second end in the second compartment, and a second conduit section having a first end in the second compartment and a second end coupled to the settling container; and transporting the fluid comprises injecting a fluid into the first conduit section to generate a first flow and injecting a fluid into the second conduit section to generate a second flow, the first flow drawing abrasive particles from the first compartment and the second flow drawing abrasive particles from at least the second compartment.
 34. The method of claim 33 wherein injecting a fluid into the conduit sections comprises: pressurizing a gas; and introducing the gas into the conduit sections below a fluid level.
 35. The method of claim 33 wherein injecting a fluid into the conduit sections comprises pumping a liquid through the conduit sections.
 36. The method of claim 30, further comprising clearing an inlet of a conduit between the compartment and the settling container of an accumulation of abrasive particles.
 37. The method of claim 36 wherein clearing the conduit inlet comprises: closing a back-flush valve in the conduit; and injecting air into the conduit between the back-flush valve and the abrasive particle accumulation, the injected air blowing the abrasive particle accumulation from the inlet of the conduit. 